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The three main types of ground frost are radiation frost , advection frost (advection hoar frost) and evaporation frost. The latter is a rare type which occurs when surface moisture evaporates into drier air causing its temperature at the surface to fall at or under the freezing point of water. [1]
Drying starts at the bottom of the bin, which is the first place air contacts. The dry air is brought up by the fan through a layer of wet grain. Drying happens in a layer of 1 to 2 feet thick, which is called the drying zone. The drying zone moves from the bottom of the bin to the top, and when it reaches the highest layer, the grain is dry.
Lake-effect snow is produced during cooler atmospheric conditions when a cold air mass moves across long expanses of warmer lake water, warming the lower layer of air which picks up water vapor from the lake, rises up through the colder air above, freezes, and is deposited on the leeward (downwind) shores.
A virga, also called a dry storm, is an observable streak or shaft of precipitation that evaporates or sublimates before reaching the ground. [1] A shaft of precipitation that does not evaporate before reaching the ground is known in meteorology as a precipitation shaft .
Overview of the cryosphere and its larger components [1]. The cryosphere is an umbrella term for those portions of Earth's surface where water is in solid form. This includes sea ice, ice on lakes or rivers, snow, glaciers, ice caps, ice sheets, and frozen ground (which includes permafrost).
In construction, the thaw depth is a major factor in ensuring the structural integrity of the objects in question. The primary factor that determines the thaw depth is the maximal air temperature. The soil type is another important factor: coarser textures of the parent material have higher thermal conductivity , and, e.g., sandy soils have ...
Each white lump marks the top of a deep ground-freezing tap. Cross section of a ground freezing pipe as used in the Big Dig. Ground freezing is a construction technique used in circumstances where soil needs to be stabilized so it will not collapse next to excavations, or to prevent contaminants spilled into soil from being leached away. [1]
Cryoturbation is the dominant force operating in the active layer, and tends to make it generally uniform in composition throughout. However, variation in the composition of soils due to differences in parent rock are very marked in permafrost regions due to the low rate of weathering in the very cold climate.